261315822080 has 160 divisors (see below), whose sum is σ = 660735567360. Its totient is φ = 98842705920.

The previous prime is 261315822071. The next prime is 261315822091. The reversal of 261315822080 is 80228513162.

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28060625 + ... + 28069935.

It is an arithmetic number, because the mean of its divisors is an integer number (4129597296).

Almost surely, 2^261315822080 is an apocalyptic number.

261315822080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261315822080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (330367783680).

261315822080 is an abundant number, since it is smaller than the sum of its proper divisors (399419745280).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261315822080 is an equidigital number, since it uses as much as digits as its factorization.

261315822080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9930 (or 9914 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The spelling of 261315822080 in words is "two hundred sixty-one billion, three hundred fifteen million, eight hundred twenty-two thousand, eighty".